System and method of displaying a video stream

ABSTRACT

The present disclosure is generally directed to a video stream processing system and to a method of displaying a video stream. In a particular embodiment, the method includes receiving a video stream to be displayed on a display device. During a first time period, a low resolution version of the video stream is displayed while a full resolution version of the video stream is being recovered. The method further includes synchronizing the low resolution version of the video stream with the full resolution version of the video stream, and, during a second time period after the first time period, switching between display of the low resolution version of the video stream to display of the full resolution version of the video stream.

FIELD OF THE DISCLOSURE

The present disclosure relates to a system and method of displaying a video stream.

BACKGROUND

In a variety of situations in which television content is transmitted digitally, there can be a significant delay that occurs when switching from one source of video to another. Typically, the delay occurs while changing a television channel, but the delay also may occur when starting a new video stream in a number of situations. The delay depends on the specific situation, such as the type of video compression, the network bandwidth, and the decompression hardware. Further, the delay can occur when a new network stream is initiated and the delay can also occur when accessing video that is stored locally at Digital Video Recorder (DVR), a Personal Video Recorder (PVR), other local video storage device. Customers and users find this delay disconcerting. Moreover, the delay is of particular concern since analog televisions do not exhibit this type of delay.

Certain proposed solutions to the delay may be defined to fall into two classes. The simplest approach is to provide access to videos through a user interface that effectively hides the delay. This is the approach used by a variety of products in which the customer is effectively encouraged to navigate trough an Electronic Program Guide (EPG) and avoid directly switching channels. This method does not really solve the problem; it simply encourages the user to behave in a manner that causes the delay to be less noticeable. The second approach is to overpower the delay by bursting a very large amount of video data in a short amount of time. This technique requires the transmission of up to 10 times the normal amount of data in order to provide sufficient video data to begin rendering the video in a short amount of time after a channel is changed (e.g. less than 100 msec).

Both of these approaches attempt to address the problem of video delays, but the first requires customers' to change their behavior and the second places significant and expensive requirements on the local network and the rendering device.

Accordingly, there is a need for an improved system and method of displaying a video stream.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a video processing system;

FIG. 2 is a flow chart that illustrates a first embodiment of a method of displaying a video stream;

FIG. 3 is a flow chart that illustrates a second embodiment of a method of displaying a video stream; and

FIG. 4 is a flow chart that illustrates a third embodiment of a method of displaying a video stream.

DETAILED DESCRIPTION OF THE DRAWINGS

The present disclosure is generally directed to a video stream processing system and to a method of displaying a video stream. In a particular embodiment, the method includes receiving a video stream to be displayed on a display device. During a first time period, a low resolution version of the video stream is displayed while a full resolution version of the video stream is being recovered. The method further includes synchronizing the low resolution version of the video stream with the full resolution version of the video stream, and, during a second time period after the first time period, switching between display of the low resolution version of the video stream to display of the full resolution version of the video stream.

In a particular embodiment, the video stream processing system includes a user interface to detect a channel change request; a video detection module responsive to the user interface, and a video generation module responsive to the video detection module. The video detection module is to receive a video stream to be displayed on a display device. The video generation module is to communicate to the display device a first version of the video stream while the video detection module recovers a second version of the video stream. The first version of the video stream has a lower video display quality than the second version of the video stream. The video generation module includes synchronization logic to synchronize the first version of the video stream with the second version of the video stream, and the video generation module switches between communicating the first version of the video stream to communicate the second version of the video stream to the display device.

Referring to FIG. 1, a video stream processing system is illustrated and is designated 100. The video stream processing system 100 includes a video processing system 102 coupled via a communication link 120 to a video display device 130, such as a television. An example of an appropriate communication link is a coaxial cable. The video processing system 102 includes a video input 110 and includes a remote control interface 108. The remote control interface 108 receives signals, such as infrared signals 114, from a remote control device 112. The video processing system 102 further includes a video stream detection module 106 and a video generation module 104. The video stream detection module 106 receives the video input 110 and is responsive to signals received at the remote control interface 108.

The video stream detection module 106 forwards detected and processed video streams to the video generation module 104. The video generation module 104 provides a video signal to be communicated over the coaxial cable 120 for display at the video display device 130.

In a particular embodiment, the remote control device 112 provides a channel request signal to request a channel change. The channel request signal may be communicated using the infrared or other wireless communication signal 114 to the remote control interface 108. The remote control interface 108 then communicates the received channel change request to the video stream detection module 106. The video stream detection module 106, in turn, tunes to the requested channel within the video input 110. Further, the video stream detection module 106 provides instructions and processed signals to the video generation module 104. Then, the video generation module provides a video image signal that corresponds to the newly selected channel.

Referring to FIG. 2, a particular embodiment of a method of displaying a video stream is illustrated. The method includes detecting a channel change request, at 202. The method further includes receiving a video stream to be displayed on a display device, at 204. Further, the method includes displaying a low resolution version of the video stream on a display device during a first time period while recovering a full resolution version of the video stream, as shown at 206. Typically, the first time period is in the range of 1-3 seconds, based on the delay. As illustrated in FIG. 2, the method further includes the step of synchronizing the low resolution version of the video stream with the full resolution version of the video stream, as shown at 208. During a second time period, at 210, the method includes switching between the display of the low resolution version of the video stream to display of the full resolution version of the video stream. The second time period occurs after the first time period. Optionally, the method includes temporarily displaying a blurred image on the display device while switching between the low resolution version of the video stream to the full resolution version of the video stream, as shown at 212.

Referring to FIG. 3, another embodiment of a method of displaying a video stream is illustrated. The method includes detecting a channel change request, at 302, and receiving a video stream to be displayed on a display device, at 304. The method further includes, during a first time period, displaying a first version of the video stream on a display device while recovering a second version of the video stream, at 306. Typically, the first time period is in the range of 1-3 seconds based on the delay. In a particular exemplary embodiment, the video generation module 104 provides a low resolution version of the video stream of the newly selected channel while the video stream detection module 106 is processing the video stream to recover a full resolution version.

In a particular illustrative embodiment, an audio signal is provided to the display during the first time period and the audio signal is provided with full resolution such that a video display device user hears full audio while the first version of the video stream is being displayed. In a particular embodiment, the first version of the video stream has a lower video display quality than the second version of the video stream. For example, the first version of the video stream may have a reduced color set when compared to the second version of the video stream. As another example, the first version may have a reduced spectral frequency or other visual parameter that is degraded when compared to the second version of the video stream. Thus, the first version of the video stream consumes less bandwidth and may be displayed on the display device more quickly in response to the channel change request.

The method further includes synchronizing the first version of the video stream with the second version of the video stream, as shown at 308. During a second time period after the first time period, the method includes switching between the display of the first version of the video stream to the display of the second version of the video stream, as shown at 310. Optionally, during a third time period, the method includes displaying a third version of the video stream where the third version has a higher video display quality than the second version of the video stream. In a particular example, the first, second, and third versions of the video stream together comprise a portion of a progressive video stream. The progressive video stream initially presents a low quality image and then, presents added resolution and higher quality images over a sequence of successive time periods.

Referring to FIG. 4, another exemplary embodiment of a method of displaying a video stream is illustrated. The method includes detecting a channel change, at 402, and receiving a video stream to be displayed on the display device, at 404. During a first time period, a still image is displayed, as shown at 406. The still image is associated with the video stream. The still image is displayed while recovering the full motion video stream after the request for the channel change. During a second time period after the first time period, the method includes switching between display of the still image to display of the video stream as a full motion video, as shown at 408. In a particular illustrative embodiment, an audio signal is provided to the display during the first time period and the audio signal is provided with full resolution such that the video display device user hears full audio while the still image is being displayed. In another embodiment, the still image may comprise a title screen associated with the video stream or may include a frame derived from the video stream. The title screen may include information regarding the video stream such as the title of an episode, the title of a series, or the title of a movie that is to be displayed on the screen.

While particular illustrative methods of displaying a video stream have been described, it should be understood that many alternate methods may also be used with the system illustrated in FIG. 1. In a particular illustrative embodiment, the first period of time when a low resolution video stream is displayed may be less than three seconds. In another embodiment, a full resolution audio signal is provided to the display device during the first period of time while displaying the low resolution version of the video stream, such as when displaying a still image or a degraded or reduced bandwidth type video stream as illustrated. In a particular exemplary embodiment, the first time period in which a low resolution version of a video stream is displayed occurs within 100 milliseconds after detecting a channel change request, such as a channel change request initiated by a user of the remote control device 1 12 shown in FIG. 1. Thus, a user surfing through channels of a display device may quickly determine the particular content of individual channels.

Previous methods of handling channel change requests for digital video have produced significant delays. Ignoring such delays can negatively impact a customer perception of service quality. Since this is a significant and negative departure from previous customer experiences with analog television signals, such delays are undesirable. The methods described provide a user experience with reduced delay, and allows the user to quickly determine desirability of continuing to watch a particular channel. Thus, the disclosed method and system offers an improved video user experience.

The above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments which fall within the true spirit and scope of the present invention. Thus, to the maximum extent allowed by law, the scope of the present invention is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description. 

1. A method of displaying a video stream, the method comprising: receiving a video stream to be displayed on a display device; during a first time period, displaying a low resolution version of the video stream while recovering a full resolution version of the video stream; synchronizing the low resolution version of the video stream with the full resolution version of the video stream; and during a second time period after the first time period, switching between display of the low resolution version of the video stream to display of the full resolution version of the video stream.
 2. The method of claim 1, wherein the display device is a television.
 3. The method of claim 1, wherein the first period is less than three seconds.
 4. The method of claim 1, wherein a full resolution audio signal is provided to the display device during the first time period while displaying the low resolution version of the video stream.
 5. The method of claim 1, wherein a video quality of the full resolution version of the video stream is higher than a video quality of the low resolution version of the video stream.
 6. The method of claim 1, further comprising temporarily displaying a blurred image while switching between the low resolution version to the full resolution version of the video stream.
 7. The method of claim 1, further comprising detecting a channel change request and wherein the first time period begins within one hundred milliseconds after detecting the channel change request.
 8. A method of displaying a video stream, the method comprising: detecting a channel change; receiving a video stream corresponding to a changed channel, the video stream to be displayed on a display device; during a first time period, displaying a first version of the video stream while recovering a second version of the video stream, the first version of the video stream having a lower video display quality than the second version of the video stream; synchronizing the first version of the video stream with the second version of the video stream; and switching between display of the first version of the video stream to display the second version of the video stream.
 9. The method of claim 8, further comprising during a third time period, displaying a third version of the video stream, the third version having higher video display quality than the second version.
 10. The method of claim 9, wherein the first version, the second version, and the third version together comprise a progressive stream of the video stream.
 11. The method of claim 8, wherein the video stream is an encoded digital video signal.
 12. The method of claim 8, wherein the first version has a reduced color set than the second version.
 13. The method of claim 8, wherein the first version has a reduced spectral frequency than the second version.
 14. The method of claim 8, wherein the first version has a degraded visual parameter with respect to the second version.
 15. The method of claim 8, wherein the first time period begins no more than 100 milliseconds after the detected channel change.
 16. A method of displaying a video stream, the method comprising: detecting a channel change; receiving a video stream to be displayed on a display device; during a first time period, displaying a still image associated with the video stream while recovering the video stream; and switching between display of the still image to display of the video stream as a full motion video display.
 17. The method of claim 16, wherein an audio signal is provided to the display device during the first time period.
 18. The method of claim 16, wherein the still image comprises a title screen.
 19. The method of claim 16, wherein the still image comprises a frame from the video stream.
 20. A video stream processing system comprising: a user interface to detect a channel change request; a video detection module responsive to the user interface, the video detection module to receive a video stream to be displayed on a display device; a video generation module responsive to the video detection module, the video generation module to communicate to the display device a first version of the video stream while the video detection module recovers a second version of the video stream, the first version of the video stream having a lower video display quality than the second version of the video stream, the video generation module including synchronization logic to synchronize the first version of the video stream with the second version of the video stream; and wherein, the video generation module switches between communicating the first version of the video stream to communicate the second version of the video stream to the display device.
 21. The system of claim 20, wherein the first version is a low resolution version of the video stream and the second version is a higher resolution version of the video stream.
 22. A video stream processing system comprising: a user interface responsive to a channel change request; a video detection module responsive to the user interface, the video detection module to receive a video stream to be displayed on a display device; and a display generation module responsive to the video detection module and coupled to the display device, the display generation module to generate a still image associated with the video stream while the video detection module is recovering the video stream, and after a time period, the display generation module switches between generation of the still image to generation of the video stream for display as a full motion video on the display device. 